This invention relates generally to self-aligning spherical bearings and, more particularly, to heavy duty spherical bearings with solid liners as used, for example, in rod end bearings.
Generally, rod end bearings used in aircraft controls and similar applications require a self-aligning configuration with a solid liner of bronze, brass, polymer, fabric or other bearing material supported by a close fitting steel housing. Snap-together assemblies utilizing resilient liners of nylon or similar material result in spherical bearings that do not provide sufficient strength for these demanding applications and do not satisfy the rigorous military specifications.
One method currently used to fabricate heavy duty spherical bearings employs a machined cylindrical sleeve with radially inwardly extending end flanges restricting the end opening of the entrance face. After a liner is manually positioned on the recessed cylindrical surface between the flanges, the sleeve is coined around the ball part of the bearing in a large press, causing the liner to conform, generally, to the shape of the ball part. The bearing is then cured and machined.
Such fabrication requires a long process time, 24 hours or more including the curing step, and often results in an irregular liner which may trap dirt and have non-uniform contact points, affecting performance. The required tedious labor and large press add to the high cost of manufacture. And, due to the distortion caused during coining of the sleeve, the length and diameter of the sleeve must be machined to the sleeve's finished dimensions after assembly of the bearing.
The foregoing illustrates limitations known to exist in present spherical bearings. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.